New salicidation technology with Ni(Pt) alloy for MOSFETs

Abstract

A novel salicide technology to improve the thermal

stability of the conventional Ni silicide has been developed by employing

Ni(Pt) alloy salicidation. This technique provides an effective

avenue to overcome the low thermal budget (<700 °C) of

the conventional Ni salicidation by forming Ni(Pt)Si. The addition

of Pt has enhanced the thermal stability of NiSi. Improved

sheet resistance of the salicided narrow poly-Si and active lines was

achieved up to 750 °C and 700 °C for as-deposited Ni(Pt) thickness

of 30 nm and 15 nm, respectively. This successfully extends the

rapid thermal processing (RTP) windowby delaying the nucleation

of NiSi2 and agglomeration. Implementation of Ni(Pt) alloyed silicidation

was demonstrated on PMOSFETs with high drive current

and low junction leakage.